Abstract: The detection and determination of (a) hydrogen peroxide or of a substance which reacts with the formation of hydrogen peroxide or (b) of peroxidase or a peroxidatively active substance, is carried out by contacting an unknown sample with a chromogen and, in case (a), with a peroxidatively active substance or in case (b) with hydrogen peroxide or a substance which reacts with the formation of hydrogen peroxide, and evaluating the coloration produced by the reaction, wherein, as the chromogen, there is used at least one 3,3',5,5'-tetraalkylbenzidine compound of the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which can be the same or different, are straight-chained or branched alkyl radicals containing up to 6 and preferably up to 4 carbon atoms.

Abstract: Novel 3-aminocarbazole compounds of the formula: ##SPC1##WhereinX is hydrogen or halogen,Y is oxygen or represents two hydrogen atoms; andR.sub.1 and R.sub.2, which can be the same or different, are hydrogen, lower alkyl or hydroxyalkyl or amino; andN is 1 or 2, with the proviso that when n is2, X, Y, R.sub.1 and R.sub.2 cannot all be hydrogen atoms, as well as the salts thereof with inorganic and organic acids; are outstandingly effective indicators for the determination of glucose and provide stable compositions for such glucose determination.

Abstract: Novel 3-aminocarbazole compounds of the formula: ##SPC1##WhereinX is hydrogen or halogen,Y is oxygen or represents two hydrogen atoms; andR.sub.1 and R.sub.2, which can be the same or different, are hydrogen, lower alkyl or hydroxyalkyl or amino; andn is 1 or 2, with the proviso that when n is 2, X, Y, R.sub.1 and R.sub.2 cannot all be hydrogen atoms,As well as the salts thereof with inorganic and organic acids; are outstandingly effective indicators for the determination of glucose and provide stable compositions for such glucose determination.

Abstract: Glucose contained in urine is determined by contacting a sample with a diagnostic composition comprising an absorbent carrier impregnated with glucose oxidase, peroxidase, an indicator compound such as o-tolidine, and as a buffer, 2-(N-morpholino)-ethane-sulfonic acid.

Abstract: 9-(.gamma.-AMINOPROPYL)-3-AMINOCARBAZOLE, WHEN INCORPORATED INTO INDICATOR COMPOSITIONS ALSO COMPRISING OXIDATION INDICATORS SUCH AS O-TOLIDINE FOR THE ENZYMATIC DETECTION OF GLUCOSE, RESULTS IN OUTSTANDINGLY STABLE INDICATOR COMPOSITIONS AND NOT ADVERSELY EFFECTED BY NORMALLY INTERFERING COMPONENTS IN THE TEST SAMPLE.